1. Field of the Invention
The present invention relates to a liquid jet head and a liquid jet apparatus.
2. Description of the Related Art
The present invention relates to a liquid jet head and a liquid jet apparatus. More particularly, the present invention relates to an ink jet recording head and an ink jet recording apparatus in which a vibration plate is formed by a portion of a pressure generating chamber which is communicated with a nozzle opening ejecting ink droplets therefrom, and a piezoelectric element is formed on a surface of the vibration plate so that the ink droplets are ejected by the displacement of the piezoelectric element.
As the ink jet recording head, a structure having a flow path forming substrate which has formed therein at least two rows of pressure generating chambers communicated with nozzle openings and a bonding substrate which is bonded to the flow path forming substrate at a side where piezoelectric elements are formed and on which a driving IC for driving the piezoelectric elements is mounted is known.
In such an ink jet recording head, a configuration is known in which the vibration plate consists of a silicon oxide layer and a zirconium oxide layer and the piezoelectric element consists of a lower electrode, a piezoelectric layer, and an upper electrode. Further, a configuration is known in which a pattern region of the layers constituting the piezoelectric element is covered with an insulating protective film formed of an inorganic insulating material.
When moisture contained in ink or the like enters into an interface of the silicon oxide layer and the zirconium oxide layer, the interface peels off to destroy the vibration plate, so that the performance of the vibration plate deteriorates.
Such problems are similarly found in other liquid jet heads ejecting droplets of different liquid other than ink as well as the ink jet recording head ejecting ink droplets.